Jermaine Joseph, of Conway Road in Harringay, insisted Seydou Diarrassouba, 18, was the aggressor and had threatened to attack him with a blade. He denied murder and was cleared by a jury.

A second man, Thulani Khumalo, of Eade Road in South Tottenham, was cleared of the same charge partway through the case due to lack of evidence.

Joseph, 23, stabbed Diarrassouba twice inside a Footlocker store in a fatal clash lasting just seconds on December 26. The victim staggered outside but collapsed and was pronounced dead less than an hour later from a stab wound to his heart.

The attack arose out of bad blood between those associated with two notorious south London street gangs. Diarrassouba, nicknamed ‘Nutz’ because of his violent nature, had been a member of the ABM - or All ‘Bout Money - gang since around 2007 and had been involved violence and robberies with weapons, the court heard.

The ABM gang has been linked to dozens of violent attacks in recent years, including the shooting of five-year-old Thusha Kamaleswaran, who was blasted in the chest by members of the Brixton-based GAS - or Guns And Shanks - gang hunting down drug dealer and ABM member Shaun Bryan in a dispute over territory.

Joseph had been a member of a second rival clan, the O31 - or ‘O-Tray’ - also based around Stockwell, but had moved to Tottenham to try and escape his violent past.

The former gang member claimed to have clashed with Seydou on previous occasions and to have been chased by him and his associates.

Joseph denied murder, claiming the victim had a knife and had tried to stab him, but was convicted after a trial at the Old Bailey.

Joseph admitted plunging the blade into his victim’s chest but insisted he had been acting in self-defence after Diarrassouba tried to stab him.

He said of the victim: “He was the aggressor. He chased me. He came to attack me. I only did what I had to do in self defence.

“I stabbed him to stop him from stabbing me. I tried to escape the situation.”

Comparing himself to a cat being chased by a dog, he said: ‘It’s like a dog chasing the cat, the cat still shows his claws.’

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